合并两个COUNT总计而不使用公共字段

Question

我正在寻找一些建议来组合来自不同表的两个COUNT的总和的最佳方法，使用每个表中没有共同字段名称的字段。

目前我有两个单独的查询，可以计算外观和替换，如下所示。

外观

SELECT
  P.PlayerID AS id, COUNT(A.AppearancePlayerID) AS apps
FROM 
  sports_seasons S
LEFT OUTER JOIN sports_players P ON P.PlayerID = S.SeasonPlayerID AND S.SeasonID = '$seasonid'
LEFT OUTER JOIN sports_appearances A ON A.AppearancePlayerID = S.SeasonPlayerID AND A.AppearanceSeasonID = '$seasonid'
WHERE 
  P.PlayerID != ''
GROUP BY id
ORDER BY id

替换

SELECT
   P.PlayerID AS id, COUNT(SU.SubstitutionPlayerIDIn) AS subapps
FROM 
   sports_seasons S
LEFT OUTER JOIN sports_players P ON P.PlayerID = S.SeasonPlayerID AND S.SeasonID = '$seasonid'
LEFT OUTER JOIN sports_substitutions SU ON SU.SubstitutionPlayerIDIn = S.SeasonPlayerID AND SU.SubstitutionSeasonID = '$seasonid'
WHERE 
  P.PlayerID != ''
GROUP BY id
ORDER BY id

我目前的尝试如下：

SELECT P.PlayerID AS id,    
  (
  SELECT
    COUNT(A.AppearancePlayerID) AS apps
  FROM 
    sports_seasons S
  LEFT OUTER JOIN sports_players P ON P.PlayerID = S.SeasonPlayerID AND S.SeasonID = '$seasonid'
  LEFT OUTER JOIN sports_appearances A ON A.AppearancePlayerID = S.SeasonPlayerID AND A.AppearanceSeasonID = '$seasonid'
  WHERE 
    P.PlayerID != '' AND P.PlayerPublish != 0
  )
  +
  ( 
  SELECT
    COUNT(SU.SubstitutionPlayerIDIn) AS subapps
  FROM 
    sports_seasons S
  LEFT OUTER JOIN sports_players P ON P.PlayerID = S.SeasonPlayerID AND S.SeasonID = '$seasonid'
  LEFT OUTER JOIN sports_substitutions SU ON   SU.SubstitutionPlayerIDIn = S.SeasonPlayerID AND SU.SubstitutionSeasonID = '$seasonid'
  WHERE 
    P.PlayerID != '' AND P.PlayerPublish != 0               
  ) AS total
FROM sports_players P
GROUP BY id
ORDER BY id

可悲的是，我没有在哪里。

以下是正在使用的表格。 DB是运动队球员出场记录。

PlayerID | PlayerName // Players table

AppearanceID | AppearancePlayerID | AppearanceSeasonID // A table collating first team appearance made

SubstitutionID | SubstitutionPlayerIDIn | SubstitutionSeasonID // A table collating substitution appearances made

SeasonID | SeasonPlayerID // A table handling registrations

使用MySQL 5.6。

Answer 1

您可以使用它们作为派生表将两个查询的结果连接起来。我认为INNER JOIN就足够了。

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